What does the mass number of an element tell you about its atoms?

Question

helpp!

Answer 1

MASS NUMBER:

the number of protons + neutrons

ATOMIC NUMBER:

the number of protons

Answer 2

It tells you how many nucloens (protons and neutrons) there are in the nucleus.

Answer 3

Simple, it is the number of protons and neutrons in a nucleus of an atom.

The atomic number is the number of protons in an atom, and as an atom must be nucleus, we can thus figure out the number of electrons e.g 5 protons, there are 5 electrons, and by this we can work out the number of neutrons

Answer 4

Hey..Good question...!

You can get ol information on : http://en.wikipedia.org/wiki/Atom#Mass

and much of it is interesting too....

Thanx........Good Luck !

Answer 5

It tells you, roughly, how much each atom weighs in atomic mass units.  Only roughly because of nuclear energy effects.

The mass number is equal to the number of protons plus number of neutrons. Strictly, it is not a property of the element but of one of its isotopes.  The number of neutrons in the nucleus is then the difference between the atomic number and the mass number.  For example, 12C has six neutrons in the nucleus, but 13C has seven and 14C (the isotope used in radio carbon dating) has eight.